United States and Israeli strikes on Iran open the war — Key Events — Iran–Gulf

What happened

A large-scale United States and Israeli strike campaign against Iran begins. The Congressional Research Service records more than ten thousand targets struck in Iran by 25 March, and reports the operation's cost as exceeding $11.3bn in its first six days — a figure it notes excludes many associated costs. Iranian retaliation against Israel, United States facilities and Gulf states begins the same day.

The physical opening of the current campaign, and the date from which every other 2026 record in this module is measured. No authorisation for the use of military force was obtained, and measures directing the removal of United States forces were rejected in both congressional chambers in March.

Confidence: High

When28 Feb 2026

KindMilitary · Weapons deliveries

Confidence: High Sources: Congressional Research Service — Iran, the Gulf and the Strait of Hormuz Methodology Corrections

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Watch questions this event bears on

Standing analytical questions whose evidence runs through this event, each with its latest review. Derived from the Watch object, never restated here.

Military2026-10-18Does one headquarters command both of Iran’s armed forces, or coordinate them?
Unchanged
1. 2026-09-04: Baseline
2. 2026-09-13: No material change
3. 2026-09-20: No material change
4. 2026-09-27: No material change
5. 2026-10-04: No material change
6. 2026-10-05: Observable met
7. 2026-10-18: No material change

Connected records

10 records that this event names, or that name it — every one an explicit reference in a published record, nothing inferred from subject matter.

Part of1

Campaigns whose record places this event inside them.

The 2026 warOpening and closure

Actors3

Actor records this event names.

Participants5

Organisations this event records, with the role and confidence it states.

Analytical Notes1

Published Notes whose analysis names this record. The Note owns the edge; this is the way back to it.

Who commands Iran's war? Coordination is on the record. Command below the top is notLeadership & institutions2026-10-05

Where this fits

This is one entry in the Iran–Gulf timeline. The full Key Events surface carries every dated turning point with its filters and its essential subset, and this event in place shows what came before and after it. How Vigil grades, dates and sources its claims is set out in the methodology.